Papers by Maximina Romero
Journal of Asian Ceramic Societies, May 26, 2020
F-richterite based glasses in the SiO 2 -CaO-MgO-Na 2 O-F system were investigated by X-ray diffr... more F-richterite based glasses in the SiO 2 -CaO-MgO-Na 2 O-F system were investigated by X-ray diffraction, differential scanning calorimetry and field emission scanning electron microscopy to ascertain the influence of fluorine content on preferential crystallization mechanism and on the spatial position of crystals developed in the initial steps of glass devitrification. The results highlight that both surface and volume mechanisms occur in the crystallization of fluorrichterite glasses. However, these glasses preferentially devitrify by a surface crystallization mechanism, although an increase of fluorine content leads to a modification in the location of the first developed crystals.
desde su fundación no sólo ha realizado a lo largo de su ya larga historia investigaciones y vali... more desde su fundación no sólo ha realizado a lo largo de su ya larga historia investigaciones y valiosas aportaciones científicas y técnicas en el campo de los materiales cerámicos y vidrios, sino que además fue uno de los principales fundadores de la actual Sociedad Española de Cerámica y Vidrio (SECV) con la destacada participación de D. Francisco Arredondo y Verdú. En los últimos once años esta línea de investigación se ha visto reforzada con la creación del Grupo y Laboratorio de Materiales Vítreos y Cerámicos, por lo que se realiza una revisión de la relación de este centro con este tipo de materiales, recordándose los investigadores y publicaciones que más destacaron en este camp. Se realiza finalmente un análisis de la situación actual y de las perspectivas de I+D+i en este tipo de materiales de construcción, haciendo especial énfasis en sus aplicaciones en fachadas ventiladas y del factor dinamizador de la investigación científica que implicará el reto tecnológico de la aplicación de plaquetas cerámicas en este tipo de fachadas.
Boletin De La Sociedad Espanola De Ceramica Y Vidrio, Oct 30, 2005
Recycling of industrial wastes for value-added applications in clay-based ceramic products: a global review (2015–19)
Elsevier eBooks, 2020
Abstract In recent years, ceramics have played very significant roles in the immobilization of po... more Abstract In recent years, ceramics have played very significant roles in the immobilization of potentially hazardous waste. Currently, this technology is making a strong impression as an extremely advantageous processing technique for the consolidation of ceramics for the immobilization of waste. The heterogeneity of traditional clay-based materials accommodates a variety of wastes with no major loss of the properties of the final product. Consequently, some researchers have developed new applications using this waste as a clay-based ceramic material, that is, tiles (clay and porcelain stoneware), bricks, and even as lightweight aggregates. An initial description and characterization of the different wastes is summarized. The review also includes brief summaries of the different applications researched between 2015 and 2019, highlighting how they work when the waste is added to the ceramic. An evaluation of the environmental implications is also given. The analysis and evaluation of the vast amount of experimental research have shown that these varieties of waste are potentially valuable as a ceramic material resource for the manufacture of clay-based ceramic products, where waste can be used as a substitute for expensive natural resources, improving the products’ physical, mechanical, and environmental performance, with no significant environmental impacts.
Springer eBooks, 1999
CIP Data applied for Die Deutsche Bibliothek -CIP-Einheitsaufnahme Characterization techniques of... more CIP Data applied for Die Deutsche Bibliothek -CIP-Einheitsaufnahme Characterization techniques of glasses and ceramics / J. Ma. Rincon ; M. Romero (eds.).
Thermal behaviour and characterization of an iron aluminum arsenate mineral
Journal of Thermal Analysis and Calorimetry, 2004
It has been determined the thermal behaviour at high temperatures of an iron aluminum arsenate mi... more It has been determined the thermal behaviour at high temperatures of an iron aluminum arsenate mineral first described in the location of La Serena Valley, Extremadura, Spain, which expands until 1173 K contracting later and softening at 1653 K and full melting at 1773 K. The DTA/TG experiment only detects some rearrangement with an endothermic at 1173 K due to
Materials Research Bulletin, Aug 1, 1998
The nucleation and crystallization of thin layers of glasses (glazes) over ceramic substrates dur... more The nucleation and crystallization of thin layers of glasses (glazes) over ceramic substrates during the fast firing of tiles for pavements and wall tiles has been a topic of great interest for tile and ceramic paving industries in recent years. Here a wide range of glass-ceramic compositions having different types of crystallization microstructure has been investigated. Based on observations by scanning electron microscopy and energy-dispersive X-ray microanalysis, several aspects of nucleation and crystallization of these new types of glass-ceramic glazes are presented and discussed.
Microstructural characterization of a goethite waste from zinc hydrometallurgical process
Materials Letters, May 1, 1997
The different hydrometallurgical processes for the metallic zinc recovery produce a high quantity... more The different hydrometallurgical processes for the metallic zinc recovery produce a high quantity of wastes in the form of muds that at the moment are stored within the production plants in large clamps without until now may have been found an effective way for their recycling. A possible solution for these wastes would be the utilization of the vitrification and
Basis and Applications of High Resolution Electron Microscopy (HREM) for the Characterization of Ceramics and Glass-Ceramics
The microstructure characterization of ceramics, traditional and advanced, as well as glass-ceram... more The microstructure characterization of ceramics, traditional and advanced, as well as glass-ceramics can be nowadays investigated by modern transmission electron microscopes which allow high resolution microstructure views of the crystalline phase details that constitute these materials to be obtained. From the lattice fringes to the network images very valuable information can be obtained by the use of the two or multi-beam electron illuminations giving direct information from crystalline structures, ordering effects, internal defects, twinning, transformation of phases, interfaces etc. After a summary reviewing the fundamentals of this type of electron microscopy, several examples are shown, as well as problems that can be afforded by HREM in ceramics and glass-ceramics.
Perspectivas de avances científicos y tecnológicos en plaquetas cerámicas para la construcción
Se realiza una revisión de los materiales cerámicos que se utilizan como material estructural, de... more Se realiza una revisión de los materiales cerámicos que se utilizan como material estructural, de revestimiento tanto exterior como interior y auxiliar en sistemas constructivos de la edificación. y en especial en los referentes a su uso en fachadas ventiladas. Se dan las características y denominaciones fundamentales de este tipo de materiales y se comentan las exigencias básicas del CTE respecto a los mismos.Por último, las recientes tendencias y novedades en estos materiales se revisan, así como su evolución para los próximos años con vistas a una construcción más sostenible medioambientalmente Abstract A review of ceramics in the building construction systems is discussed showing the main applications as structural material, as covering and paving (both in external and internal uses), as well as the uses in ventilated façades. The main characteristics and fundamental types in ceramics are given, as well as the basic regulations with respect these materials in the Building Technical Code (CTE in the Spanish law). Lately, the recent trends and innovations from these materials in new products are reviewed, as well as the evolution prevented in the next year with respect a more environmental sustainable construction industry
The growth of mullite (3Al 2 O 3 •2SiO 2 ) in a porcelain stoneware body for tiles production has... more The growth of mullite (3Al 2 O 3 •2SiO 2 ) in a porcelain stoneware body for tiles production has been investigated using differential thermal analysis (DTA). The activation energy calculated by both isothermal and non-isothermal treatments is 599 and 622 kJ mol -1 respectively. The growth morphology parameters n and m are both about 1.5 indicating that bulk nucleation is dominant in mullite crystallization followed by three-dimensional growth of mullite crystals with polyhedron-like morphology controlled by diffusion from a constant number of nuclei. The frequency factor calculated by the isothermal treatment is equal to 8.21 x 10 22 s -1 .
Materiales De Construccion, Dec 30, 2001
Basis and Applications of Convergent Beam Electron Diffraction (CBED) for the Investigation of Phases in Ceramics and Glass-Ceramics
Springer eBooks, 1999
The convergent beam electron diffraction (CBED) technique, as well as the electron microdiffracti... more The convergent beam electron diffraction (CBED) technique, as well as the electron microdiffraction methods are currently used in analytical electron microscopy for materials characterization. These diffraction methods allow the identification of very small crystalline phases and tri-dimensional crystallographic analysis with high spatial resolution through the application of a very thin electron beam and wide diffraction angle through the specimen in a transmission electron microscope (TEM). Despite the wide range of analytical possibilities, its use in the characterization of ceramics, glass-ceramics and their raw materials has been scarce. Therefore, in this chapter are shown the basic principles of CBED as well as microdiffraction for the crystallographic analysis of ceramics both from our own research and by reviewing some examples of applications from the literature.
Boletin De La Sociedad Espanola De Ceramica Y Vidrio, Feb 28, 2000
El proceso vitrocerámico, así como el procesado habitual de materiales cerámicos y vítreos, está ... more El proceso vitrocerámico, así como el procesado habitual de materiales cerámicos y vítreos, está siendo actualmente investigado como una prometedora vía para el aislamiento, inertización e incluso el reciclado de residuos minerales (escombreras y estériles de minas, desmontes de Obras Públicas, etc...) e industriales (lodos, fangos, escorias, cenizas, etc... ). A partir de residuos inorgánicos de diferente naturaleza (lodos de la hidrometalurgia del zinc, cenizas de centrales térmicas, escorias y cenizas de plantas incineradoras) así como de mezclas de los mismos con otras materias primas, se están obteniendo materiales sintéticos con amplias aplicaciones en la Construcción y en Obras Públicas. Los resultados que se están consiguiendo permiten concluir que los procesos cerámico y vitrocerámico se perfilan como una alternativa real y útil para resolver, al menos parcialmente, los problemas sociales y medioambientales asociados a la producción de dichos residuos.
Construction and Building Materials, Jun 1, 2005
The microstructure characterization and mechanical properties of a reinforced cement by the intro... more The microstructure characterization and mechanical properties of a reinforced cement by the introduction of polypropylene fibres creating a composite material with a reduction of the weight and possible regulation of the times of setting has been carried out. A detailed microstructure determination has been made first time by environmental scanning electron microscopy and field emission scanning electron microscopy. The final surface of this composite after setting is different according to the contacts areas of mold, while the bulk microstructure is very homogeneous, depicting uniform distribution of fibres into the matrix.
Materials Research Bulletin, 2001
The crystallisation behaviour of vitrified industrial waste (fly ash from domiciliary solid waste... more The crystallisation behaviour of vitrified industrial waste (fly ash from domiciliary solid waste incineration) was examined by differential thermal analysis, X-ray diffractometry and scanning electron microscopy. It was demonstrated that powder processing route was required to transform the vitrified industrial waste into glass-ceramics products. Time-Temperature-Transformation (TTT) diagrams were drawn for the two main crystalline phases, diopside and wollastonite. The wollastonite existed in both monoclinic and triclinic forms and an iron-rich phase was also observed at the boundaries between glass particles. The morphology of the crystalline phases and the development of microstructure were observed as a function of heat treatment time and temperature. The optimum heat treatment was 900ºC for 40-50 minutes.
Applied Clay Science, Nov 1, 2005
The substitution of clayey raw materials urban sewage sludge in the production of traditional cer... more The substitution of clayey raw materials urban sewage sludge in the production of traditional ceramics could give place to a cost saving due to the utilisation of wastes as secondary raw material. At the same time, it can help to solve the environmental problems associated to such wastes. This research shows the results of the substitution of clay for sewage sludge in different proportions in a ceramic body. The sludge characterisation has been carried out by an analytical protocol. After that, the most suitable products were selected regarding to the chemical composition and the technological characterisation of the resulting ceramic material.
Journal of The European Ceramic Society, Oct 1, 1999
This paper reports the results of a study of the feasibility of recycling the solid residues from... more This paper reports the results of a study of the feasibility of recycling the solid residues from domiciliary waste incineration by producing a glass-ceramic. The major components of the raw material (TIRME F+L), which was from a Spanish domiciliary incinerator, were CaO, SiO 2 and Al 2 O 3 but nucleating agents, such as TiO 2 , P 2 O 5 , and Fe 2 O 3 were also present in reasonable amounts. It was found that a relatively stable glass with suitable viscosity could be obtained by mixing 65 wt% TIRME F+L with 35 wt% glass cullet. The heat treatment required to crystallise the glass produced from this mixture, designated TIR65, was nucleation at 560°C for 35 min followed by crystal growth at 100°C for 120 min. The resulting glass-ceramic contained a number of crystalline phases, the most stable being clinoenstatite (MgSiO 3 ), or perhaps a pyroxenic phase which incorporates Ca, Mg and Al in its composition, and åkermanite (Ca 2 MgSi 2 O 7 ). The microstructure contained both fibre-like and dendritic crystals. The mechanical properties were acceptable for applications such as tiles for the building industry.
Modified Porcelainized Stoneware Tiles Obtained from Recycling of Granite and MSW Incinerator Fly Ashes
Key Engineering Materials, Dec 1, 2001
Key Engineering Materials Vols. 206-213 (2002) pp 847-850 Online available since 2001/Dec/15 at w... more Key Engineering Materials Vols. 206-213 (2002) pp 847-850 Online available since 2001/Dec/15 at www.scientific.net © (2002) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/KEM.206-213.847 ... All rights reserved. No part of ...
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Papers by Maximina Romero